The present invention relates to a method for recovering a signal representing the phase difference between a local carrier signal and the carrier of an amplitude and/or phase shift keyed received signal, with the received signal being divided into two cartesian oriented signal components which are a function of the phase difference and which are in a quadrature relationship to one another, and with these two signal components together representing one of the possible signal states.
Such a method is described, for example, in the article by A. Leclert and P. Vandamme, "Universal Carrier Recovery Loop for QASK and PSK Signal Sets," in IEEE TRANSACTIONS ON COMMUNICATIONS, Vol. COM-31, No. 1, January 1983, pages 130-136, for the recovery of a control signal for a voltage controlled oscillator which is used to recover the carrier in a demodulator circuit for amplitude and/or phase shift keyed (QASK) signals. A control signal generated according to this prior art method, which represents the phase difference between two carrier signals, falsely indicates some phase differences as 0.degree. when they do in fact differ substantially from 0.degree..